The present invention relates to a method of controlling a dictionary/directory of a database system, the control including alteration, addition, deletion and the like of the dictionary/directory.
In some database systems, a dictionary/directory system is provided which is used for defining the structure of a database and for controlling access to the database.
A dictionary/directory system is described, for example, in "Computer Surveys" Vol. 14, No. 2, June 1982, pp. 245-275 published by Association for Computing Machinery.
A dictionary stores definition information defining the structure of a database. A directory is obtained by converting part of the definition information stored in the dictionary into the form of a table which can be referenced easily during execution of a user program.
The dictionary is subjected to an addition, alteration or deletion process when changing the structure of the database. The directory is also changed so as to follow such process for the dictionary. Conventionally, the record of any change in the database has not been kept as a log.
Therefore, it has been difficult to ensure agreement between the contents of dictionary and directory, or when a dictionary is partially changed in its content, it has been difficult to correct the associated information in the dictionary and directory.